It began quietly, in the early hours of a Tennessee morning, and ended in twisted metal on a highway.

A woman who authorities say fatally shot her husband while he slept, critically wounded her son, and then deliberately crashed into an 18-wheeler on Interstate 155 has died from her injuries, the Dyer County Sheriff’s Office confirmed Thursday.

The woman was identified as 60-year-old Sherry Darlene Lydon. Her husband, William John Lydon Jr., also 60, was pronounced dead at the family’s home. Their 24-year-old son remains hospitalized after being shot, deputies said.

In a statement, the sheriff’s office described the case as “a deeply disturbing situation” that has shaken the community.

According to investigators, the violence began Thursday morning when Sherry Lydon allegedly shot her husband while he was sleeping. She then turned the gun on her son, critically injuring him before fleeing the home in a Dodge Charger.

The son was rushed to a hospital in critical condition. Authorities have not released his name.

After leaving the residence, deputies say Lydon drove onto Interstate 155, where she collided head-on with an 18-wheeler in what investigators described as “an apparent attempt to commit suicide.” She suffered catastrophic injuries and was transported to a hospital, where she later died.

Sheriff Jeff Box said preliminary findings indicate Lydon had recently undergone surgery to remove a tumor and had been experiencing severe mental health symptoms in the weeks leading up to the shootings.

“She was reportedly experiencing night terrors, anxiety, and sleep disturbances,” the sheriff’s office said, adding that those factors are being considered as investigators work to understand what led to the tragedy.

Both the home and the crash site remain active crime scenes as detectives piece together the sequence of events. Authorities emphasized that there is no ongoing threat to the public.

“This is an incredibly tragic situation that has affected our community deeply,” Sheriff Box said. “Our thoughts and prayers are with the Lydon family during this difficult time.”

Box also used the moment to urge residents to look out for one another, particularly when mental health concerns arise.

“If you see something strange, report it,” he said. “If it’s something with mental health — if you know somebody or got a family member like that and they’re not getting treatment — check on them. Help them follow up on things like this.”

The driver of the 18-wheeler was not reported injured.

Investigators cautioned that details could change as the investigation continues. Anyone with information related to the case is urged to contact the Dyer County Sheriff’s Office at 731-285-2802.